Children grow up stronger if their mothers had increased amounts of vitamin D while pregnant, a study has found.

Scientists made the discovery after recording levels of vitamin D in the blood of 678 women in the later stages of pregnancy.

When their children were four years old, their grip strength and muscle mass were measured.

Results showed that the higher levels of vitamin D were in the mother, the greater the child's grip strength. A similar though less pronounced correlation was seen with muscle mass.

Lead scientist Dr Nicholas Harvey, from the Medical Research Council Lifecourse Epidemiology Unit at the University of Southampton, said: "It is likely that the greater muscle strength observed at four years of age in children born to mothers with higher vitamin D levels will track into adulthood, and so potentially help to reduce the burden of illness associated with loss of muscle mass in old age."